West Ham are expected to confirm the appointment of Graham Potter as their new head coach after sacking Julen Lopetegui on Wednesday.
Potter is poised to replace the 58-year-old on a two-and-a-halfyear deal after West Ham held further positive talks with the former Chelsea and Brighton boss on Tuesday.
West Ham have called a press conference for 9am on Thursday morning at the London Stadium.
Potter - who could take charge of a tough FA Cup third-round trip to Aston Villa on Friday - is set to return to management 20 months since he was sacked by Chelsea just seven months and 31 matches into a five-year contract.
Lopetegui had arrived at Rush Green early on Wednesday and took training in the morning before seeing his pre-match press conference ahead of the FA Cup clash against Aston Villa cancelled, which was scheduled for 1.15pm.
The announcement of his exit, after just eight months in charge of the club, was then made at 3.15pm.
A club statement read: "The first half of the 2024/25 season has not aligned with the club's ambitions and the club has therefore taken action in line with its objectives."
West Ham added: "The process of appointing a replacement is under way."
Lopetegui took over at the London Stadium in May, replacing David Moyes after his contract came to an end at the conclusion of the 2023/24 season.
Despite overseeing a summer transfer spend in excess of £130m, Lopetegui won just six of his 20 Premier League matches in charge and the Hammers are currently 14th in the table.
Lopetegui was close to the sack in December when the club's board were split 60-40 over whether to axe him following a 3-1 defeat to Leicester.
He oversaw a 2-1 victory over Wolves in his next game but won just once in the following five matches and West Ham have now ended his tenure, with his last game a 4-1 defeat at Manchester City.
Sky Sports News' Kaveh Solhekol:
"It's difficult to find any West Ham supporters who think Julen Lopetegui should have been given more time. He has been fighting to save his job for months now and it seemed inevitable that the end would come sooner rather than later.
"Lopetegui will argue that he needed more time to implement the change in style of play required after the departure of David Moyes in the summer. He may have a point but ultimately it felt like this would be a wasted season if he stayed in his job.
"There were a few good performances and results - the 2-0 November win at Newcastle United stands out - but overall his employers could just not understand why West Ham were conceding so many goals.
"Lopetegui's side let in 39 goals in 19 league games and that was unacceptable, especially considering the amount of money that was spent on transfers in the summer.
"West Ham were determined to make sure they appointed the right person to replace David Moyes but it is obvious now they made a big mistake with Lopetegui.
"Apparently, he got the job after a very impressive interview. West Ham fans will be hoping Graham Potter does more than just talk a good game."
"Graham Potter, waiting in the wings, has agreed terms on a two-and-a-half-year contract. He was waiting for West Ham to do what they have done and parted ways with Lopetegui.
"The timing works for both. West Ham need a bit of stability right now. It's a good fit because Graham Potter wants a project. He's ready to get back into mangement.
"I think the owners and fans will like his brand of football, the fact that he promotes youth, the fact he likes a progressive style.
"But can he get that instant success? Five of their next seven Premier League matches are London derbies - and in the middle of those is a return to Stamford Bridge."
Sky Sports News reporter Dharmesh Sheth:
"I think there will be quite a lot of eyeballs on sporting director Tim Steidten. Julen Lopetegui was the unanimous choice among the board to take over as West Ham manager; if you speak to some fans, they felt a little bit underwhelmed by the appointment. Now he's gone, you'd think there's going to be a bit of pressure on Steidten.
"They spent over £100m in the summer, and he was central to that recruitment. By definition, because Lopetegui has gone, you can almost call those first few weeks a bit of a failure and what they looked like in the transfer window.
"Looking ahead to this transfer window, I think it's going to be really interesting to see the kind of deals West Ham do and even more scrutiny on their sporting director."
Sky Sports' Jamie Carragher speaking on Monday Night Football:
"They played quite well in an attacking sense [against Manchester City] but West Ham have let themselves down time and time again defensively.
"Whenever they get beat, they get beat badly. They're a mess at the back. There's no doubt the manager's position has been precarious but when you think of that scoreline at the weekend, that's the sixth time this season in the Premier League that they've lost a game by three goals or more. In the Carabao Cup, they lost 5-1 to Liverpool.
"When teams get beaten badly, I always think there's something wrong in the dressing room. It's how you lose. I was expecting this three or four weeks ago."
January 10: Aston Villa (a), FA Cup, kick-off 8pm
January 14: Fulham (h), Premier League, kick-off 7.30pm
January 18: Crystal Palace (h), Premier League, kick-off 3pm
January 26: Aston Villa (a), Premier League, live on Sky Sports, kick-off 4.30pm
February 3: Chelsea (a), Premier League, live on Sky Sports, kick-off 8pm
